CN114622821A

CN114622821A - Multifunctional ladder frame structure

Info

Publication number: CN114622821A
Application number: CN202011461139.8A
Authority: CN
Inventors: 杨明舜
Original assignee: Formosa Saint Jose Corp
Current assignee: Formosa Saint Jose Corp
Priority date: 2020-12-11
Filing date: 2020-12-11
Publication date: 2022-06-14
Also published as: WO2022121233A1; EP4180616A4; KR20220084014A; GB2613714A; GB202302266D0; CA3150628A1; JP2023513992A; JP7285607B2; EP4180616A1; AU2021394086A1

Abstract

The invention relates to a multifunctional ladder frame structure, which comprises: a first ladder frame; a second ladder frame; and a pivot assembly combined with the second ladder frame and the first ladder frame, wherein the multifunctional ladder frame structure can be further provided with a foot bar combined with the ladder frame, and the webbing can be adjusted or the length of the foot bar can be adjusted. By the implementation of the invention, the multifunctional ladder frame structure can be inserted and fixed between the wheel arch and the tire to be used as a tire ladder frame, and can also be formed into an A-shaped ladder which is arranged beside an automobile or the tire or used in other places; the adjustable braid can be added, the stability of the vehicle tire ladder frame can be improved when the adjustable braid is sleeved on the tire, the ladder frame which is sleeved and folded by the adjustable braid can be more properly fixed without turning outwards, the danger is avoided, and the ladder frame is convenient to store or transport; the multifunctional ladder frame structure can be immediately applied to tires with different sizes or different tread widths, uneven road surfaces or inclined road surfaces or object surfaces; the treading height of the A-shaped ladder can be increased when the A-shaped ladder is used.

Description

Multifunctional ladder frame structure

Technical Field

The present invention relates to a ladder frame structure, and more particularly to a multifunctional ladder frame structure having various characteristics, which can be used as a tire ladder frame or an a-shaped ladder frame and is applicable to various types of vehicles.

Background

With the proliferation of automotive recreational applications, the use of recreational vehicles, and even larger vehicles, has been a trend to gradually surpass the demand for smaller vehicles. However, since the models of recreational vehicles, cross-border vehicles, and pickup trucks are usually high, and it is necessary to take out and place devices from the top of the vehicle or to clean and maintain the vehicles, the needs of the ladder rack for vehicles are needed.

However, the conventional ladder frames sold in the market or used in the technical field of vehicles have only a single function, or can be only used as a common ladder frame or can be only used together with vehicles, and the folding and storage are still not perfect regardless of the stability during use or not in use, but the ladder frames slide and topple over, even the ladder frames cannot stand stably due to the unevenness of the ground so as to cause danger.

In view of this, how to invent a new one that can be set up and operated simply; when in use, the ladder can be used as a tire ladder frame and firmly inserted and fixed between an automobile wheel arch and a tire, or can be used as an A-shaped ladder and firmly stand beside an automobile or a tire or other required places; when being stored, stored or transported, the utility model can be fixed properly and will not turn outward at will to cause danger; even can be immediately applied to various tires with different tread widths and can be applied to various different vehicle types; and can be used in many functional ladder structures of progress efficiency such as the road surface of level and unevenness or slope immediately, not only to whole car application field and industry, will be an important breakthrough innovation and progress, to the vast car user, also provide a exciting and high safe application choice.

Disclosure of Invention

The invention relates to a multifunctional ladder frame structure, comprising: a first ladder frame; a second ladder frame; and a pivot assembly combined with the second ladder frame and the first ladder frame, wherein the multifunctional ladder frame structure can be further provided with a foot bar combined with the ladder frame, and the webbing can be adjusted or the length of the foot bar can be adjusted. By the implementation of the invention, the multifunctional ladder frame structure can be inserted and fixed between the wheel arch and the tire to be used as a tire ladder frame, and can also be formed into an A-shaped ladder and arranged beside an automobile or the tire or other places for use; the adjustable woven belts can be added, the stability of the vehicle tire ladder frame can be improved when the ladder frame is sleeved on the tire, the ladder frame cannot slip from a gap between the inserted wheel arch and the tire, the ladder frame which is sleeved and folded by the adjustable woven belts can be more properly fixed, cannot be turned outwards, avoids danger and is convenient to store or transport; the foot rods which can respectively adjust the using length are added, so that the multifunctional ladder frame structure can be immediately applied to tires with various sizes or different tread widths, uneven road surfaces or inclined road surfaces or object surfaces; the top pipe or the additional second treading part can further increase the treading height of the A-shaped ladder when in use.

The invention provides a multifunctional ladder frame structure, which comprises: a first ladder frame comprising: the top pipe is an inverted U-shaped firm pipe body; two first longitudinal pipes which are arranged in the same direction and are fixedly connected with two ends of the top pipe respectively by one end, and the other end of each first longitudinal pipe is provided with a pipe orifice; at least one first treading part which is fixedly arranged between the two first longitudinal pipes in a crossing way; and two first snap fasteners which are respectively and fixedly arranged on the first longitudinal pipe; a second ladder frame comprising: two second longitudinal pipes formed by firm pipe bodies and arranged corresponding to the first longitudinal pipes, wherein each second longitudinal pipe is provided with a pipe orifice; two second snap fasteners which are respectively fixedly arranged on the second longitudinal pipe and respectively correspond to the two first snap fasteners; and at least one transverse treading pipe which is a firm pipe body and is fixedly crossed between the two second longitudinal pipes; and two pivot assemblies respectively fixedly arranged at the fixed connection positions of the top pipe and the two first longitudinal pipes and together rotatably and pivotally connecting the second ladder frame to the first ladder frame.

Preferably, a cross bar is further connected to the joint of the two first longitudinal pipes and the top pipe.

Preferably, a plurality of leg pipes are further provided, and are inserted into the first longitudinal pipe or the second longitudinal pipe from the pipe opening one by one and are slid or fixed on the first longitudinal pipe or the second longitudinal pipe.

Preferably, at least one fixing protrusion is disposed on any one of the leg tubes, and a plurality of positioning holes corresponding to the fixing protrusions are disposed on any one of the first longitudinal tube or the second longitudinal tube.

Preferably, the two pivot assemblies pivotally connect the second ladder frame to the first ladder frame in a rotatable manner by riveting or screwing respectively.

Preferably, the second ladder frame is fixed to the two pivot assemblies and forms a tire ladder frame with an included angle together with the first ladder frame.

Preferably, the second ladder frame is fixed to the two pivoting assemblies and forms an A-shaped ladder frame with an included angle together with the first ladder frame.

Preferably, an adjustable braid is further provided, spanning the two first longitudinal pipes and having two ends respectively fixed to the two first longitudinal pipes.

Preferably, a second stepping part is further provided and fixed across the top pipe.

Preferably, the two first longitudinal pipes are formed by bending and extending from two ends of the top pipe in the same direction.

By implementing the invention, the multifunctional ladder frame structure can at least achieve the following multiple special effects:

the ladder frame can be inserted and fixed between the wheel arch and the tire and used as a tire ladder frame.

And secondly, the ladder can be formed into an A-shaped ladder and is arranged beside an automobile or a tire or other required places.

When the multifunctional ladder frame is used as an A-shaped ladder, the U-shaped top pipe or the additionally arranged second treading part can increase the treading height, so that the practicability and the convenience of the multifunctional ladder frame structure are improved.

And fourthly, an adjustable braid is added to be sleeved on the surface of the tire, so that the stability of the ladder frame can be improved, and the ladder frame cannot slip out of the inserted wheel arch.

And fifthly, the adjustable braid can be sleeved on the second ladder frame, so that the tire ladder frame can be well fixed in a folding state, can not turn outwards, avoids danger and is more convenient to store, store or transport.

Sixthly, each additional foot rod can independently and respectively adjust the using length, so that the multifunctional ladder frame structure can be immediately matched and used for tires with various sizes or different tread widths, or uneven, uneven or inclined road surfaces or object surfaces.

So that those skilled in the art can readily understand the technical disclosure and practice the invention, and can readily understand the objects and advantages of the invention based on the disclosure, claims and drawings, the detailed features and advantages of the invention will be described in detail in the embodiments.

Drawings

Fig. 1 is a perspective view of a multi-functional ladder frame structure according to an embodiment of the present invention.

Fig. 2A is a schematic perspective view of a first ladder frame according to an embodiment of the invention.

Fig. 2B is a perspective view of a second ladder rack according to an embodiment of the invention.

Fig. 2C is a schematic perspective view of a pivot assembly pivoting a first ladder frame and a second ladder frame according to an embodiment of the invention.

Fig. 3 is a schematic perspective view of a cross bar connected to a fixed joint of two first vertical pipes and a top pipe of the first ladder frame according to the embodiment of the present invention.

Fig. 4A is a schematic perspective view of a multi-functional ladder frame structure further provided with a plurality of legs according to an embodiment of the present invention.

Fig. 4B is a perspective view of another multi-functional ladder frame structure further provided with a plurality of legs according to the embodiment of the present invention.

Fig. 5A is a schematic perspective view of a leg bar with a fixing protrusion and a first vertical tube or a second vertical tube with a corresponding positioning hole according to an embodiment of the invention.

Fig. 5B is a schematic perspective view of another leg bar of the present invention having a fixing protrusion and a corresponding positioning hole on the first longitudinal tube or the second longitudinal tube.

Fig. 6A is a perspective view of a multi-function ladder structure formed as a tire ladder according to an embodiment of the present invention.

Fig. 6B is a perspective view of a multi-functional ladder frame structure formed as an a-shaped ladder according to an embodiment of the present invention.

Fig. 7 is a perspective view of a multi-purpose ladder frame structure further provided with an adjustable webbing according to an embodiment of the present invention.

Fig. 8 is a schematic perspective view of the first ladder frame and the second ladder frame being folded and the webbing straps being adjustable to fix the second ladder frame according to the embodiment of the present invention.

Fig. 9 is a perspective view of a multifunctional ladder frame structure disposed between a wheel arch and a tire and using an adjustable webbing to increase stability according to an embodiment of the present invention.

Fig. 10A is a perspective view of the multifunctional ladder frame structure further provided with a second stepping member according to the embodiment of the invention.

Fig. 10B is a perspective view of a multi-function ladder frame structure formed by extending the first tread member as the second tread member according to the embodiment of the present invention.

Fig. 11 is a schematic perspective view of a multifunctional ladder frame structure formed by bending and extending the first longitudinal pipe from two ends of the top pipe in the same direction according to an embodiment of the present invention.

Fig. 12 is a schematic perspective view of another multifunctional ladder frame structure formed by bending and extending the first longitudinal pipe from two ends of the top pipe in the same direction according to the embodiment of the present invention.

[ description of main element symbols ]

100: multifunctional ladder frame structure 10: first ladder frame

11: the top pipe 12: first longitudinal pipe

121: the pipe orifice 13: first treading part

14: first fastener 20: second ladder frame

21: second longitudinal pipe 211: pipe orifice

22: the second fastening member 23: pedal horizontal tube

30: the pivoting assembly 40: cross bar

50: the foot bar 60: fixed convex part

70: positioning hole 80: adjustable ribbon

90: second tread member θ: included angle

810: tire 820: wheel arch

Detailed Description

So that the reader can more easily understand and understand the technical means and operation of the present invention, the embodiments are described in detail below with reference to the drawings.

First, referring to fig. 1, a multi-functional ladder frame structure 100 of an embodiment includes a first ladder frame 10; a second ladder frame 20; and a pivot assembly 30.

Referring to fig. 1 and 2A, the first ladder frame 10 includes: a top pipe 11; two first longitudinal tubes 12; at least one first tread member 13; and two first fastening members 14.

As shown in fig. 1 and 2A, the top pipe 11 is a strong n-shaped pipe body, and the top pipe 11 may be a metal pipe, an alloy pipe, or a durable pipe body made of polymer material.

Referring to fig. 1 and fig. 2A, two first vertical tubes 12 are disposed in the same direction, and are respectively fixed to two ends of the n-shaped top tube 11 by one end, and the other end of each first vertical tube 12 is further provided with a tube opening 121. The first vertical pipe 12 is fixed to the top pipe 11 in such a way that an included angle is formed between the first vertical pipe 12 and the n-shaped top pipe 11.

The material of the first longitudinal pipe 12 can be selected to be the same as that of the top pipe 11, and in a specific preferred embodiment, the first longitudinal pipe 12 can be integrally formed with the top pipe 11. In addition, the two first longitudinal tubes 12 can be formed in parallel or nearly parallel.

As shown in fig. 1 and fig. 2A, the distance between two first vertical pipes 12 is selected such that the first ladder frame 10 is inserted into a gap between a tire 810 and a wheel arch 820 of an automobile from the two first vertical pipes 12 in a manner that the pipe opening 121 faces the tire 810, and is disposed over the tire 810.

As shown in fig. 1 and 2A, at least one first stepping member 13 is disposed between the two first vertical pipes 12 and is fixed to the two first vertical pipes 12. The first treading member 13 of the embodiment can be formed by combining one treading surface or more than two treading tubes, and the treading surface can be a solid mesh treading surface, a flat plate treading surface or a solid treading surface with a plurality of holes; if the first stepping member 13 is formed by selecting at least two stepping tubes, the stepping tubes form a stable stepping plane together. Of course, the first stepping member 13 may be made of a material having anti-slip property for increasing the safety of use.

As shown in fig. 1 and fig. 2A, the first fastening members 14 are respectively fixed to two first longitudinal pipes 12, and each first longitudinal pipe 12 is fixed with one first fastening member 14. Any one of the first fastening members 14 used in the embodiments can be selected from a link, a hook, a bendable link, a bendable hook, or a webbing with a buckle or a button hole.

Referring to fig. 1 and fig. 2B, the second ladder frame 20 of the multi-functional ladder frame structure 100 includes two second vertical tubes 21; two second fastening members 22; and at least one tread cross tube 23.

As shown in fig. 1 and fig. 2B, the second longitudinal pipes 21 are disposed corresponding to the first longitudinal pipes 12, the second longitudinal pipes 21 are also formed of rigid pipes, the two second longitudinal pipes 21 can be disposed in parallel or nearly parallel, and one end of each second longitudinal pipe 21 is provided with a pipe opening 211.

The thickness or size of the second longitudinal tube 21 can be selected to be the same as or similar to the thickness or size of the first longitudinal tube 12, and the distance between the two second longitudinal tubes 21 measured from any position can be selected to be equal to the distance between the two first longitudinal tubes 12 at the corresponding position.

As shown in fig. 1 and fig. 2B, the second fastening members 22 are respectively fixed to the two second longitudinal pipes 21, and each of the second fastening members 22 is correspondingly fastened to or separated from one of the first fastening members 14.

That is, by fastening or separating the two corresponding second fastening members 22 and the two corresponding first fastening members 14, the second longitudinal pipe 21 and the first longitudinal pipe 12, and further the second ladder frame 20 and the first ladder frame 10 can be connected or separated at the second fastening members 22 and the first fastening members 14.

Referring to fig. 1 and 2B, at least one transverse stepping tube 23 fixedly disposed between the two second longitudinal tubes 21 is a rigid tube, and two ends of the transverse stepping tube 23 are respectively and fixedly connected to the two second longitudinal tubes 21, that is, the transverse stepping tube 23 is fixedly disposed between the two second longitudinal tubes 21 in a crossing manner for stepping and ascending.

Referring to fig. 1 and fig. 2C, two pivot assemblies 30 of the multi-functional ladder frame structure 100 are respectively fixed at the fixed connection positions of the top tube 11 and the two first longitudinal tubes 12, and the two pivot assemblies 30 jointly pivot and connect the second ladder frame 20 to the first ladder frame 10.

Thus, the first ladder frame 10 and the second ladder frame 20 are combined together into the multi-functional ladder frame structure 100 through the pivoting of the two pivoting assemblies 30, and the second ladder frame 20 can be firmly fixed to the first ladder frame 10, or the second ladder frame 20 can rotate separately or together relative to the first ladder frame 10 by using the pivoting assemblies 30 as axes.

As for the way of the pivot assembly 30 to pivot the first ladder frame 10 and the second ladder frame 20, the second ladder frame 20 can be selected to be connected to the first ladder frame 10 by riveting or screwing.

Next, referring to fig. 3, the first ladder frame 10 may further be provided with a cross bar 40, and the cross bar 40 is fixedly connected to the fixed connection between the two first vertical pipes 12 and the pi-shaped top pipe 11. This makes the first ladder frame 10 and the entire multi-function ladder frame structure 100 more stable in use.

As shown in fig. 4A and 4B, the multi-function ladder frame structure 100 may further include a plurality of leg bars 50, regardless of whether the cross bar 40 is provided or not, and the leg bars 50 may be inserted into the first vertical pipe 12 or the second vertical pipe 21 from one

pipe opening

121 or 211 one by one.

In an embodiment, the foot of the foot bar 50 can extend out of the nozzle 121 or the nozzle 211, and the foot of the foot bar 50 can be selected to have a larger friction force or a more elastic material, so that the multifunctional ladder frame structure 100 can stand more stably or can be inserted between the wheel arch 820 and the tire 810 less easily to damage the tire 810 or the vehicle body.

As shown in fig. 5A and 5B, each leg rod 50 can slide or be fixed on one of the first longitudinal tubes 12 or one of the second longitudinal tubes 21. At least one fixing protrusion 60 can be fixedly disposed on the leg bar 50, and each first longitudinal tube 12 or each second longitudinal tube 21 is provided with a plurality of positioning holes 70 corresponding to the size and position of the fixing protrusion 60.

Therefore, each leg bar 50 can be individually slid on the first longitudinal tube 12 or the second longitudinal tube 21, or can be fixed to the first longitudinal tube 12 or the second longitudinal tube 21 in such a manner that the fixing protrusion 60 is engaged with one of the positioning holes 70.

Thus, each leg rod 50 can respectively extend out from the first longitudinal tube 12 or the second longitudinal tube 21 with the same or different lengths, so that the two first longitudinal tubes 12 and the two second longitudinal tubes 21 in the multi-functional ladder frame structure 100 are equal to or can be called as four ladder legs, and the leg rods 50 can respectively extend out with different lengths, so that the multi-functional ladder frame structure 100 can be suitable for uneven, rugged or inclined road surfaces or object surfaces, and the multi-functional ladder frame structure 100 can be matched with tires with different sizes or different tread widths of various vehicles or vehicle types.

As shown in fig. 1 and fig. 6A, the second ladder frame 20 can be fixed at two pivot assemblies 30 to form an included angle θ of more than 90 degrees with the first ladder frame 10. In this way, the first vertical pipe 12 of the first ladder frame 10 can be inserted into and fixed to the gap between the wheel arch 820 and the tire 810, so that the multi-function ladder frame structure 100 can be used as a tire ladder frame for an automobile.

As shown in fig. 1 and fig. 6B, the second ladder frame 20 can also be fixed at two pivot assemblies 30, and the second fastening member 22 is connected and fixed with the first fastening member 14, so as to form a stable a-shaped ladder together with the first ladder frame 10. The A-shaped ladder can be arranged beside a car, a tire 810 or other places where users want to arrange, and provides various application requirements.

The fixing method of the n-shaped top tube 11 and the first longitudinal tube 12 of each embodiment may be: when the multifunctional ladder frame structure 100 is used as a tire ladder frame for an automobile, the top tube 11 and the second ladder frame 20 do not interfere with each other and the use function of the tire ladder frame is not influenced; when the multi-function ladder frame structure 100 is used as an A-shaped ladder, the U-shaped top tube 11 forms a nearly horizontal plane for stepping so as to increase the overall stepping height of the A-shaped ladder.

Referring to fig. 7, the first ladder frame 10 of the multi-function ladder frame structure 100 may further be provided with an adjustable webbing 80, two ends of the adjustable webbing 80 are respectively fixed to the first longitudinal tube 12, and the length or tightness of the adjustable webbing 80 can be adjusted by a user when the adjustable webbing 80 is used.

As shown in fig. 8, when the multi-purpose ladder frame structure 100 needs to be stored, stored or transported, the first ladder frame 10 and the second ladder frame 20 can be folded and fixed, and then the adjustable webbing 80 fixed to the first ladder frame 10 is adjusted, and the adjustable webbing 80 tightly surrounds the second ladder frame 20, so that the first ladder frame 10 and the second ladder frame 20 can be closed more tightly, thereby preventing danger or inconvenience caused by being folded or separated.

As shown in fig. 9, when the multi-function ladder structure 100 is used as a tire ladder to insert and fix the first longitudinal tube 12 into the gap between the wheel arch 820 and the tire 810, the adjustable webbing 80 may be further used to cover the surface of the tire 810, thereby preventing the whole multi-function ladder structure 100 from slipping out of the gap between the inserted wheel arch 820 and the tire 810, and further improving the stability and safety of the multi-function ladder structure 100 used as a tire ladder.

Referring to fig. 10A, the multi-functional ladder frame structure 100 may further include a second step member 90 fixed across the surface of the n-shaped top tube 11 or the space surrounded by the n-shaped top tube 11. Thus, when the multi-function ladder frame structure 100 is used as an A-shaped ladder, the second stepping member 90 can effectively increase the stepping height of the A-shaped ladder.

The second treading member 90 may also be a single treading surface or a combination of two or more tubes, and the treading surface may be a solid mesh treading surface, a flat plate treading surface, or a solid treading surface with a plurality of holes; if more than two treading tube bodies are selected to form, the treading tubes mutually form a stable treading plane. Of course, the second stepping member 90 may be formed by using a material having an anti-slip property.

As shown in fig. 10B, the second stepping member 90 may also be formed by extending from the first stepping member 13, which not only increases the structural strength of the second stepping member 90 and the first stepping member 13, but also effectively simplifies the production process, and facilitates the manufacturing and production.

Furthermore, as shown in fig. 11 and 12, the first vertical tubes 12 of the multi-function ladder frame structure 100 in the above embodiments may be formed by extending and bending from the ends of the two legs of the inverted-u-shaped top tube 11 in the same direction. Thus, in addition to increasing the convenience of production or stock and smoothness of appearance, the overall structural strength of the multi-function ladder frame structure 100 may be further enhanced by reducing the number of joints between components.

As described above, as shown in the embodiments and the drawings of fig. 1 to 12, the multifunctional ladder frame structure 100 of the present invention has the special structural features, so that the multifunctional ladder frame structure 100 can be simply installed and operated; can be inserted and fixed between the wheel arch and the tire to be used as a tire ladder; can be formed into an A-shaped ladder and is arranged beside an automobile, a tire or other places; the adjustable braid 80 is additionally arranged, can be sleeved on the tire 810, can improve the stability when being used as a tire ladder frame, cannot slip out of the gap between the inserted wheel arch 820 and the tire 810, can be fixed properly when the first ladder frame 10 and the second ladder frame 20 are in a folding state, cannot be turned over or separated, is convenient to fold, store or transport and avoids danger; the length of the leg rods 50 that can be additionally arranged can be respectively adjusted, so that the multi-functional ladder frame structure 100 can be applied to various vehicle models or various tires 810 with different tread widths, and can be more stably applied to uneven, rugged or inclined road surfaces or object surfaces; the reversed U-shaped top tube 11 or the additional second stepping member 90 can further effectively increase the stepping height when the A-shaped ladder is used.

While the foregoing embodiments have been described in a specific context of preferred embodiments, it will be appreciated by those skilled in the art that the above-described embodiments are merely illustrative of the nature of the invention, which is not intended to limit the scope of the invention.

Claims

1. The utility model provides a multi-functional ladder frame structure which characterized in that, including:

a first ladder frame comprising:

a pipe-jacking, which is a n-shaped firm pipe body;

two first longitudinal pipes which are arranged in the same direction and are respectively and fixedly connected with two ends of the top pipe by one end, and the other end of each first longitudinal pipe is also provided with a pipe orifice;

at least one first treading part which is fixedly arranged between the two first longitudinal pipes in a crossing way; and

two first snap fasteners which are respectively and fixedly arranged on the two first longitudinal pipes;

a second ladder frame comprising:

two second longitudinal pipes formed by firm pipe body and set corresponding to the two first longitudinal pipes, each second longitudinal pipe is set with pipe mouth;

two second fasteners which are respectively and fixedly arranged on the two second longitudinal pipes and respectively correspond to the two first fasteners; and

at least one transverse treading pipe which is a firm pipe body and is fixedly arranged between the two second longitudinal pipes in a crossing way; and

two pivot assemblies respectively fixed at the fixed connection position of the top pipe and the two first longitudinal pipes, and pivotally connecting the second ladder frame to the first ladder frame in a rotatable manner.

2. The multi-functional ladder frame structure of claim 1, further comprising a cross bar connected to the fixed connection between the two first vertical tubes and the top tube.

3. The multi-functional ladder frame structure of claim 1, further comprising a plurality of leg tubes, one-to-one inserted into the first vertical tube or the second vertical tube from the opening, and slid or fixed on the first vertical tube or the second vertical tube.

4. The multi-function ladder frame structure of claim 3, wherein any one of the leg tubes is provided with at least one fixing protrusion, and any one of the first longitudinal tube or the second longitudinal tube is provided with a plurality of positioning holes corresponding to the fixing protrusion.

5. The multi-function ladder frame structure of claim 1, wherein the two pivot assemblies pivotally connect the second ladder frame to the first ladder frame in a riveting or screwing manner, respectively.

6. The multi-function ladder structure of claim 1 wherein the second ladder is fixed to the two pivot assemblies and forms a tire ladder with an included angle with the first ladder.

7. The multi-function ladder structure of claim 1 wherein the second ladder is fixed to the two pivoting assemblies and forms an angled a-frame with the first ladder.

8. The multi-functional ladder frame structure of claim 1, further comprising an adjustable webbing spanning the two first longitudinal tubes and having two ends respectively secured to the two first longitudinal tubes.

9. The multi-function ladder frame structure of claim 1, further comprising a second stepping member fixed across the top tube.

10. The multi-functional ladder frame structure of claim 1, wherein the two first vertical tubes are formed by bending and extending from two ends of the top tube in the same direction.